[dcdoug]

Originally Posted by computerworks

They were plumbed as a secondary pump set up from a pickup lower in the tank.

The mechanical draws fuel from a higher point; the 240's are normally off during normal operation.

The purpose was, when the tank ran low and the mechanical pump starved, the racer could throw a toggle on the dash to turn on the electrics and make it back to the pits.

The plate that has the fittings on the fuel tank would have two fittings, with one drawing fuel lower than the other.

For what it's worth, CSX6022 came set-up exactly like this. There are parallel lines with a T-fitting on the outflow side of the mechanical pump. The mechanical pickup is lower than the pickup for the twin electrics. They are off during normal driving and even at WOT I have never had a fuel starvation issue on just the mechanical.

It works exactly as designed, by the way. Given the inaccuracy of my fuel level gauge, I ran out of gas once. Sat there for a minute pissed at myself and then remembered the story of why racers had it set up this way, flipped the switch to turn on the electrics, fired back up and drove to the nearest gas station.